The Skripals were exposed to one of a family of nerve toxins known as Novichok agents that were secretly developed in the Soviet Union during the cold war. They are considered more lethal and long-lasting than the better known agents VX and sarin. “The government has concluded that it is highly likely that Russia was responsible for the act against Sergei and Yulia Skripal,” May said.

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“Either this was a direct act by the Russian state against our country, or the Russian government lost control of this potentially catastrophically damaging nerve agent and allowed it to get into the hands of others,” she added, calling the attempted murder an “indiscriminate and reckless act against the United Kingdom, putting the lives of innocent civilians at risk”. May reeled off a list of Russian offences against international sovereignty and decency, including the annexation of Crimea, hacking other countries including “meddling in elections”, and the murder using polonium of Alexander Litvinenko in London.

Jeremy Corbyn came under fire from within his own party after an equivocating response. The Labour leader condemned it as a “deeply alarming attack” but went on: “We need to continue seeking a robust dialogue with Russia on all the issues currently dividing our countries, rather than simply cutting off contact and letting the tensions and divisions get worse and potentially even more dangerous.” The Labour MP John Woodcock – a longtime Corbyn critic – praised May and made obvious reference to his leader when he warned against the UK being led by “anyone who did not understand the gravity of the threat which Russia poses”. As the investigation continues on the ground in Salisbury, a man has been jailed for 16 weeks after getting drunk and breaching the cordon around the bench where the Skripals were found – while shouting abuse about Russians.

Salt scare – Chinese takeaways and ready meals should have compulsory health warnings for their “astonishing and harmful” salt levels, health experts says. Action on Salt found the worst Chinese takeaways have five times the salt of a Big Mac while some supermarket versions have more salt than 11 bags of ready-salted crisps. It is Salt Awareness Week (get out the bunting) and heart expert Prof Graham MacGregor said: “Reducing salt is the most cost-effective measure to reduce the number of people dying or suffering from strokes or heart disease. We are now calling on Public Health England to take immediate action.” PHE agreed that “some products are still too high in salt and we know this can be reduced further”.

Worboys parole battle – A high court case to keep the “black cab rapist” John Worboys in jail begins today. Worboys, now 60, was jailed in 2009 for drugging and sexually assaulting women. The recent decision by the Parole Board to release him on licence led to a major public outcry. Two of his victims have crowdfunded their court challenge, where they will argue the board’s decision was irrational and failed to take into account all relevant issues. They are calling for the board to reveal how it came to its decision. The mayor of London, Sadiq Khan, is also involved in bringing the case to judicial review. Worboys was jailed after being convicted of 19 offences, including rape, against a total of 12 women.

Spring statement – Not about making an impact in the fashion stakes, but a preview of what the chancellor will discuss today when he gives an update on the state of the nation’s finances. Philip Hammond has promised a short and snappy summation – the real budget will come in the autumn. Hammond will be unable to boast about the UK outperforming other economies – the whole G7 has been beating us, apart from Italy. But the UK’s outlook for growth is looking marginally better than it was three months ago. Productivity is forecast to grow modestly. The government may not have to borrow to cover its day-to-day expenses this year, but the ratio of the national debt to Britain’s annual GDP sits at 85% – it was below 40% of GDP when the financial crisis began in 2007.

Trump parrots NRA policy – Donald Trump is being accused of caving in to the National Rifle Association on gun control. The president – who chastised members of Congress for being “petrified” of the NRA after the Parkland shooting – has released a school safety plan that stops short of measures such as raising the minimum age for gun purchases from 18 to 21. Instead, it talks about arming teachers to carry guns, which is the NRA’s own suggestion. White House spokeswoman Sarah Sanders said the age limit and other measures were still on the table for review, but the president was focused on “pushing through things … that we can do immediately”. The House leader of the Democrats, Nancy Pelosi, said Trump was “cravenly tiptoeing around the NRA”.

Lunchtime read: Is Corbyn’s gravitational force enough?

Could Jeremy Corbyn become prime minister? On election eve, that prospect itself, writes Rafael Behr, might do more to swing voters than any factor that can be gauged in the interim. Current polling has Labour either leading or level with the Conservatives. On preferred prime minister, Theresa May is reliably in front of Corbyn – “‘don’t know’ sometimes knocks him into third”.

But May’s leadership is shaky and she might be gone by the next election. In contrast, Corbyn has become well ensconced against challenge to his authority, writes Behr, and increasingly prime ministerial from his dress sense to how he voices his politics. “Much of British politics is a battle between rival ideas of Jeremy Corbyn … one tends to absolute wickedness, the other to infallible virtue. Neither has much resonance with the wider public. That debate has not illuminated what Corbynism means for people who don’t read manifestos or argue about politics on Twitter. So – most people.” The closer the election looms, the more “what Corbynism means”, and what the man behind it stands for, will come into play.

Business

Shares have been mixed in Asia following a lacklustre day on Wall Street. Investors are keeping a close eye on continuing tensions over the Trump tariffs. Shares in Shanghai and Hong Kong fell as China announced a revamp of its financial regulatory regime.

The pound has been trading at $1.389 and €1.126 overnight.

The papers

The Telegraph leads with the news that Theresa May has given Vladimir Putin until midnight tonight to respond to the accusation, with the Times saying the prime minister “has cleared the way for a cyberattack on Russia”. The Sun, Financial Times, the Express, the i and Scotland’s Herald all take up the ultimatum line, while the Metro declare the Novichok nerve agent was delivered “from Russia with hate”. The Mail has a different worry, asking: “How can we go to Putin’s World Cup now?”

The Mirror swerves it all, instead leading on news that the family of a girl who was spat at by Jamie Carragher doesn’t want Sky Sports to sack the football pundit.

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